Azo dyestuffs



Patented Aug. 30, 1938 UNITED STATES PATENT OFFICE AZO D-YESTUFFS Richard Stusser, Cologne, and Friedrich Muth, Leverkusen, Germany, assignors to General Aniline Works, Inc., New York, N. Y., a corporation of Delaware No Drawing. Application June 21, 1935, Serial No. 27,811. In Germany June 27, 1934 5 Claims.

wherein R stands for the radical of a diazo com- 0 pound, capable of forming heavy metal complex compounds, which may bear an azo group, such as a radical of a diazotized aromatic amine bearing in ortho-position to the diazotized amino group a metal complex forming group, such as the hydroxy group, an alkoxy group and the carboxylic-acid group stand for radicals of the benzene series, wherein OH and N=N.R stand in ortho position to each other attached to one of the benzene radicals R and R, it stands for one or two, :1: stands for S, 0, CH2 or CH=CH, and wherein the benzene radicals R and R" may bear further substituents, such as alkyl, alkoxy, halogen, the sulfonic acid group, the carboxylic acid group, the sulfone amide group and the carboxylic acid amide group, the hydrogen atoms of which may be substituted for example by alkyl or aryl.

Our new dyestuffs are obtainable by diazotizing or tetrazotizing respectively an aromatic amine, capable of forming heavy metal complex compounds and coupling with one or two equimolecular proportions respectively of a coupling component of the general formula wherein a: and n mean the same as stated above.

The dyestuifs thus obtained can be transformed in substance or on the fiber into their heavy metal complex compounds by treating with suitable metals or metal compounds, such as copper. copper hydroxide, copper salts, chromium hydroxide, chromium salts and the like. Those of our dyestuffs having water-solubilizing groups are suitable for dyeing the fiber, yielding generally brown to violetish-brown to blackish-brown shades, which when transformed into their heavy metal complex compounds are distinguished by good and fastness to fulling, carbonization and light. Those of our dyestuffs which are insoluble in water dissolve in organic solvents, such as pyridine and can be used for shading lacquers.

The invention is illustrated by the following examples, without, however, being limited thereto:-

Example 1 One molecular proportion of 6-nitro-2-aminophenol-l-sulfonic acid is diazotized and coupled in aqueous caustic alkaline solution in the presence of sodium carbonate with one molecular proportion of 3-hydroxy-diphenylene sulfide in the cold and in the presence of pyridine. After several hours the coupling mixture is acidified, some common salt is added, and the dyestuff separated is filtered and dried. It is obtained in the form of a dark powder, soluble in aqueous sodium carbonate solution, dyeing wool from an acid I lowing formula:

OH OH S I S 03H By after-treating the dyeings with bichromate there are obtained Corinth shades fast to fulling, carbonization and light.

Example 2 HOaS By after-chroming there is obtained an olive brown fast to fulling, carbonization and light.

bath; it corresponds in its free state to the fol- By substituting the 5-sulfo-2-aminobenzoic acid by one molecular proportion of 1-amino-2- hydroxy 6 nitronaphthalene 4: sulfonic acid there is obtained a dyestuff dyeing wool when after-chromed blackish-brown shades of good fastness properties.

Example 3 One molecular proportion of diazotized 4- nitro-Z-aminophenol-G-sulfonio acid is coupled in an alkaline medium with one molecular proportion of the 3-hydroxy-diphenylene oxide 2- carboxylic acid. The dyestuif having in its free state the following formula:--

OH OH 00011 l loz dyes wool when after-chromed reddish-brown shades.

In an analogous manner diazotized l-aminol- HOaS nitrobenzene G-carboxylic acid yields when coupled with 3-hydroxy-diphenylene oxide monosulfonic acid (obtained by monosulfonating 3- hydroxy-diphenylene oxide; probably the 2- sulfonic acid) a dyestufi dyeing wool yellowish brown shades, which on after-chroming are turned to dark brown.

Example 4 dyes W001 when after-chromed negro-brown shades of good fastness properties.

Example 6 20 grams of the dyestuff described in the first paragraph of Example 2 are refluxed for 10 hours in 300 cos. of water with 6 grams of a chromium chloride solution containing 270 grams of CrzOz per litre. The complex chromium compound formed is filtered and dried. It is a dark powder soluble in water, dyeing wool from an acid bath olive brown shades of good fastness to fulling, carbonization and light.

' Example 7 One molecular proportion of 6-nitro-2-amin0- phenoll-sulfonic acid is diazotized in the usual manner and coupled in an alkaline medium with one molecular proportion of 3-hydroxyphenanthrene. When the coupling is complete the reaction mass is acidified with acetic acid and the dyestuff separated is filtered and dried. It is obtained in the form of adark powder, dyeing wool from an acid bath; on after-chroming the dyeing there is obtained a grey or in the case of dark shades a black of good 'fastness to fulling, carbonization and light.

The dyestuff corresponds in its free state to the following formula:

One molecular proportion of 6-nitro-2-aminophenol-l-sulfonic acid is diazotized in the usual manner and coupled in pyridine in the presence of an alkali with one molecular proportion of 2- I l I dyes cotton brown shades which when aftertreated with a copper compound are turned to yellowish brown of good fastness to washing and light.

Example 5 One molecular proportion of diazotized 6-mitro-2-aminophenoll-sulfonic acid is coupled in a soda alkaline medium containing pyridine with one molecular proportion of 6-bromo-3-hydroxydiphenylene oxide. The dyestuff corresponding in its free state to the following formula:-

is obtained in form of a dark powder, dyeing wool reddish-brown shades, which on after-chroming are turned to olive-brown of good fastness to fulling, carbonizing and light.

I SOaH Example 9 Two molecular proportions of diazotized-nitro-2-aminophenol-6-sulfonic acid are coupled in a caustic alkaline medium containing pyridine with one molecular proportion of 3,6-dihydroxy- The dyestuff having in its 2. Water-soluble azo dyestuffs forming heavy metal complex compounds of the general formula:

diphenylene oxide. free state the following formula: E 5

NO: l| TOz N=NR wherein X stands for the radical of a diphenylene l I l oxide compound, R stands for the radical of a 1103s OH HO soan diazo compound, capable of forming heavy metal 10 OH complex compounds, OH and N=NR stand in ortho position to each other and Y stands for a water-solubilizing group selected from the class 0 consisting of the sulfonic acid and the carboxylic dyes W001 when after chromed blackisbbrown acid groups yielding generally brown to Violetish- 15 Shades brown to blackish-brown shades, which, when transformed into their heavy metal complex com- Example 10 pounds, are distinguished by good fastness to One molecular proportion of diazotized 4-nifulling, carbonization and light. 20 tro-2-aminophenol-6-sulfonic acid is coupled in 3. The water-soluble azo dyestufi having in its an alkaline medium with one molecular propor- I free state the following formula: tion of the 3-hydroxy-diphenylene oxide. The 000E OH dyestufl having in its free state the following forl OH OH Hoas N: Q 1103s g 30 NO dyeing wool from an acid bath reddish-brown 2 shades, which by after-chroming are turned to live brown fast to fulling carbonization and light. dyes wool from an acid bath brown shades which 0 by after-chroming are turned to blackish brown f g zg ?i? dyesiiufi havmg m Its 35 of good fastness to fulling, carbonization and ree S e e o owmg Ormula" light. 0H OH We claim: 1. Water-soluble azo dyestufis forming heavy metal complex compounds of the general formula: 40

' 0 OH 1 I N02 \N=NR J dyeing wool from an acid bath reddish-brown 45 wherein X stands for the radical of a diphenylene shades, which by after-chroming are turned to oxide compound, R. stands for the radical of a blackish brown fast to fulling carbonization and diazo compound, capable of forming heavy metal light. I complex compounds, OH and N=NR stand in 5. The water soluble azo dyestuff having in its ortho position to each other, n stands for one of free state the following formula: 50

R 00011 000 SOaHON\ l H the numbers one and two and Y stands for a Water-solubilizing group selected from the class consisting of the sulfonic acid and the carboxylic acid groups, yielding generally brown to violetishbrownto blackish-brown shades, which when transformed into their heavy metal complex compounds are distinguished by good fastness to fulling, carbonization and light.

dyeing cotton brown shades which by aftertreatment with a compound yielding copper are turned to yellowish brown shades of good fastness to light and washing.

RICHARD STUSSER. FRIEDRICH MUTH. 

